Phase II Trial of Gemcitabine, Prednisone, and Zoledronic Acid in Pretreated Patients with Hormone Refractory Prostate Cancer

Objectives: To investigate the impact on biochemical and objective response and on pain improvement of gemcitabine, prednisone, and zoledronic acid in patients with hormone-refractory prostate cancer (HRPC), previously treated with docetaxel-based regimens. Methods: The patients were treated with gemcitabine 1000 mg/m2 every 14 days, prednisone 10 mg orally on days 1 to 7 and 14 to 21, and zoledronic acid every 4 weeks. Changes in prostate-specific antigen levels, tumor response, and toxicity were evaluated every month. The pain response, based on pain reduction and analgesic drug reduction, was assessed during therapy. Results: A total of 22 men (median age 65 years) were treated. Overall, 5 patients (23%) achieved a 50% or greater reduction in prostate-specific antigen level after two cycles; a partial response was observed in 1 (14%) of 7 patients with measurable disease, and 3 (43%) of 7 had stable disease. Of the 22 men, 23% had pain improvement. The most important hematologic toxicity was neutropenia (grade 3 in 18%). Conclusions: The combination of gemcitabine, prednisone, and zoledronic acid appears to be associated with biochemical response, pain improvement, and good safety in pretreated patients with HRPC. © 2007 Elsevier Inc. All rights reserved.